Downhole fluid separation system

Abstract

A fluid separation system is disclosed for installation within a wellbore that penetrates a production formation and a discharge formation. The system comprises a first pump and a second pump each operatively connected to a means for operation, such as a downhole electric motor, and a fluid separator for separating wellbore fluids from the production formation into a first stream and a lighter second stream. Wellbore fluids are introduced into the first pump, and are then conveyed to an inlet of the fluid separator. The second stream exiting the fluid separator is conveyed to an inlet of the second pump, and from the second pump to the earth's surface. Devices are included, such as wellbore packers, to isolate the discharge formation from the production formation, so that the second stream exiting the fluid separator directly enters the discharge formation.

What is claimed is: 
     
       1. A fluid separation system for withdrawing fluid from a wellbore that penetrates a production formation and a discharge formation, the fluid separation system comprising: an injection pump;   a packer arrangement coupled to isolate wellbore fluids in the production formation from wellbore fluids in the discharge formation;   a fluid separator being adapted to be positioned within the wellbore adjacent the discharge formation, the injection pump being coupled to deliver wellbore fluids from the production formation to the fluid separator, the fluid separator separating the wellbore fluids into a first stream and a second stream, the first stream exiting the fluid separator and entering the discharge formation directly; and   a production pump coupled to receive the second stream and to pump the second stream to a given location.   
     
     
       2. The system, as set forth in claim 1, wherein said injection pump comprises an inlet and an outlet, said inlet being coupled to receive the wellbore fluids from the production formation and the outlet being coupled to the fluid separator. 
     
     
       3. The system, as set forth in claim 1, wherein the second stream is comprised of fluids which are lighter than fluids that comprise the first stream. 
     
     
       4. The system, as set forth in claim 1, wherein the fluid separator comprises a hydrocyclone. 
     
     
       5. The system, as set forth in claim 4, wherein the hydrocyclone comprises an inlet, a first outlet, and a second outlet, the inlet being coupled to the injection pump, the first outlet being directed to the discharge formation, and the second outlet being coupled to the production pump. 
     
     
       6. The system, as set forth in claim 1, wherein the injection pump comprises an electric motor. 
     
     
       7. The system, as set forth in claim 1, wherein said production pump comprises an electric motor. 
     
     
       8. The system, as set forth in claim 1, wherein the fluid separator comprises a plurality of hydrocyclones. 
     
     
       9. The system, as set forth in claim 8, wherein each of the plurality of hydrocyclones comprises an inlet, a first outlet, and a second outlet, the inlet being coupled to receive the wellbore fluids from the injection pump, the first outlet being directed to deposit the first stream directly in the discharge formation, and the second outlet being coupled to deliver the second stream to the production pump. 
     
     
       10. The system, as set forth in claim 1, wherein the fluid separator comprises a plurality of modular hydrocyclones coupled together. 
     
     
       11. A fluid separation system for withdrawing fluid from a wellbore that penetrates a production formation and a discharge formation, the fluid separation system being adapted to be placed into the wellbore, the fluid separation system comprising: a packer arrangement coupled to isolate wellbore fluids in the production formation from wellbore fluids in the discharge formation;   a first motor;   an injection pump coupled to the first motor;   a fluid separator being adapted to be positioned within the wellbore adjacent the discharge formation, the injection pump being coupled to deliver wellbore fluids from the production formation to the fluid separator, the fluid separator separating the wellbore fluids into a first stream and a second stream, the first stream exiting the fluid separator and entering the discharge formation directly;   a second motor being spaced from and operated independently from the first motor; and   a production pump coupled to the second motor and being coupled to receive the second stream and to pump the second stream to a the Earth's surface.   
     
     
       12. The system, as set forth in claim 11, wherein the second stream is comprised of fluids which are lighter than fluids that comprise the first stream. 
     
     
       13. The system, as set forth in claim 11, wherein the fluid separator comprises a hydrocyclone. 
     
     
       14. The system, as set forth in claim 11, wherein the fluid separator comprises a plurality of modular hydrocyclones coupled together. 
     
     
       15. The system, as set forth in claim 11, wherein the second motor is driven by the first stream exiting the fluid separator. 
     
     
       16. A fluid separation system for withdrawing fluid from a wellbore that penetrates a production formation and a discharge formation, the fluid separation system comprising: a packer arrangement coupled to isolate wellbore fluids in the production formation from wellbore fluids in the discharge formation;   a fluid separator being adapted to be positioned within the wellbore adjacent the discharge formation, the fluid separator being coupled to receive wellbore fluids from the production formation, the fluid separator separating the wellbore fluids into a first stream and a second stream, the first stream exiting the fluid separator and entering the discharge formation directly; and   a production pump coupled to receive the second stream and to pump the second stream to a given location.   
     
     
       17. The system, as set forth in claim 16, wherein the second stream is comprised of fluids which are lighter than fluids that comprise the first stream. 
     
     
       18. The system, as set forth in claim 16, wherein the fluid separator comprises a hydrocyclone. 
     
     
       19. The system, as set forth in claim 18, wherein the hydrocyclone comprises an inlet, a first outlet, and a second outlet, the inlet being coupled to receive the wellbore fluids, the first outlet being directed to the discharge formation, and the second outlet being coupled to the production pump. 
     
     
       20. The system, as set forth in claim 16, wherein said production pump comprises an electric motor. 
     
     
       21. The system, as set forth in claim 16, wherein the fluid separator comprises a plurality of hydrocyclones. 
     
     
       22. The system, as set forth in claim 16, wherein the fluid separator comprises a plurality of modular hydrocyclones coupled together. 
     
     
       23. The system, as set forth in claim 22, wherein each of the plurality of hydrocyclones comprises an inlet, a first outlet, and a second outlet, the inlet being coupled to receive the wellbore fluids, the first outlet being directed to deposit the first stream directly in the discharge formation, and the second outlet being coupled to deliver the second stream to the production pump.